docs: def _register_file_server(self, app):
          """
          File server
          Only local files can be served
          It's recommended to serve static files through NGINX instead of Python
          Use this for development only
          :param app: Flask app instance
  
          """
          if isinstance(self.driver, local.LocalStorageDriver) \
                  and self.config["serve_files"]:
              server_url = self.config["serve_files_url"].strip("/").strip()
              if server_url:
                  url = "/%s/<path:object_name>" % server_url
  
                  @app.route(url, endpoint=SERVER_ENDPOINT)
                  def files_server(object_name):
                      obj = self.get(object_name)
                      if obj is not None:
                          dl = flask_request.args.get("dl")
                          name = flask_request.args.get("name", obj.name)
  
                          if get_file_extension(name) != obj.extension:
                              name += ".%s" % obj.extension
  
                          _url = obj.get_cdn_url()
                          return send_file(_url,
                                           as_attachment=True if dl else False,
                                           attachment_filename=name,
                                           conditional=True)
                      else:
                          abort(404)
              else:
                  warnings.warn("Flask-Cloudy can't serve files. 'STORAGE_SERVER_FILES_URL' is not set")